import unittest
from feed import CheckFeed

test_channel_id = 'UCY9z_LHm2NMRJbqKl2H3Kdw'

class TestFeed(unittest.TestCase):
    def test_not_negative_ineger(self):
        with self.assertRaises(ValueError):
            CheckFeed(test_channel_id, -5)
        with self.assertRaises(ValueError):
            CheckFeed(test_channel_id, 0)
        with self.assertRaises(ValueError):
            CheckFeed(test_channel_id, '')

    def test_items_quantity(self):
        quantity = 7
        test_feed = CheckFeed(test_channel_id, quantity)
        self.assertEqual(len(test_feed.videos), quantity)

    def test_read_method_quantity(self):
        test_feed = CheckFeed(test_channel_id, 7)
        with self.assertRaises(ValueError):
            test_feed.read(-1)


    def test_nonvalid_channel_id(self):
        with self.assertRaises(ValueError):
            CheckFeed('')

